My employers want me to draft Appointment Letter in which terms should be that if employee resigns from job then he has to give three months notice and if company suddenly terminates his services then it will pay only one month's salary. According to me this condition is unreasonable as given in Section 16 of Indian Contract Act 1872 and comes under "undue influence" clause. I want to know whether we can impose such condition in Appointment Letter and if imposed then such conditions are lawfull or not. Learned members are requested to enlighten me on this matter.

Such terms will be highly inappropriate. Even if you issue appointment letter with such clause, it will not have much benefit from legal point of view; on the other hand, it can go against the employer.